New Feature: Unused code blocks are now displayed as "grayed out" in VS Code.
New Feature: Use of "yield from" generates error for Python <3.3.
New Feature: Scanning of string literals now fully complies with Python spec, including support for all defined escape sequences.
New Feature: Added "reportInvalidStringEscapeSequence" config switch to control whether the analyzer reports errors or warnings for invalid escape sequences.
New Feature: Use of Protocol in a code file is now flagged as illegal for Python <3.7.
New Feature: An attempt to instantiate certain special classes defined in typing (Callable, Generic, etc.) now emits an error.
Fixed bug in import cycle detection logic that could result in slow analysis time and even an infinite loop.